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One thing the whales did teach us is that at certain depths one can transmit low frequency sounds over thousands of miles. Unfortunately the navy's low frequency active sonar is also extremely dangerous and will either kill or fatally injure anything that gets caught within a few hundred miles of the sound blast, including whales. So thanks whales; also sorry whales. : (

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> within a few hundred miles of the sound blast With a sonar? That's incredible, do you have a source/name/something I can look up?

The deepwater sound channel conducts low frequency noise very efficiently, like a waveguide. The low frequency active sonar which the navy uses is as loud as a 747 jet engine and it can travel a very long distance through the deepwater sound channel without losing much energy. Mass beachings are still common near wherever the navy is testing it's active sonar and beached whales have been found with ruptured inner ears, though I can't find the reports now.

A lot of the navy's active sonar technology is classified so most of what we civilians know about it is based off of hydrophone measurements, autopsies of dead whales, maps of mass beaching events and whatever information the navy has made publicly available.

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